BACTERIAL CONTROL Flashcards
approaches to bacterial control?
daily life like washing/scrubbing with soaps and detergents
hospitals maintaining SOP and preventing nosocomial infections
chemical methods of microbial control*? name the principles
disinfectant
organic matter
pH
time
*compared to phenol, if more effective >1, less effective phenol coefficient is <1
name this antimicrobial term?
destruction or removal of all microbial life (including spores)
sterilization
name this antimicrobial term?
destroying and removing many vegetative pathogens from inanimate objects not including spores?
disinfection
name this antimicrobial term?
chemical destruction of vegetative pathogens in/on living tissues
antiseptics
name this antimicrobial term?
mechanical removal of microbes from limited area
degerming
name this antimicrobial term?
mechanically reduce microbial population to safe levels to eat or drink from
decontamination/sanitization
examples include bactericidal, fungicidal, virucidal and kills microbes, what is this type of solution called?
microbicides
this type of technique is aseptic and inhibits or slows growth?
microbistatic
what are the physical methods of microbial control?
temperature
filtration
radiation
osmotic pressure
what are some chemical methods of microbial control?
phenolics alcohols halogens heavy metals surfactants peroxygens aldehydes gases antimicrobial drug
what is the order of susceptibility to chemical agents for microbes, starting from most to least?
enveloped viruses fungi non enveloped viruses mycobacterial species bacterial endospores
chemical agent used for bacterial endospores?
chemical sterilants
chemical agent for mycobacterial species?
high level agents
chemical agent for non enveloped viruses?
intermediate level agents
chemical agents for fungi and enveloped viruses?
low level agents
what are the factors that influence antimicrobial action?
type of microbe number of organism environment -Temp -pH -other organic matter present -heat stability
what are the targets of antimicrobial agents?
cell membrane
DNA
proteins
mutation
what is the effect of low temperature on microbial control?
a microbiostatic that slows the metabolism
what are examples of high temp methods of physical control for microbes that use dry heat?
hot air ovens (sterilization)
incineration (direct flame)
what are examples of high temp methods of physical control for microbes that use moist heat?
boiling (time sensitive)
pasteurization
pressurized steam (autoclave)
*10 min for pathogens
this type of moist heat high temp technique kills high temp sensitive pathogens like in milk but food still spoils?
pasteurization
how are temperatures above boiling achieved?
a) sealed containers
b) increased speed of heating
c) pressure
d) use of water versus other solvents
c) pressure
what are the considerations for killing pathogens?
thermal death time
thermal death point (TDP)
this is the length of time needed to kill a population of cells at a set temperature
thermal death time
this is the minimum temperature at which a population will die in a set time usually 10 minutes
thermal death point
this is a technique used to physically remove microbes via pores for liquids or a gas? examples?
filtration like HEPA filter
mycoplasma, rickettsia, chlamydia
what does HEPA stand for in filtration?
high efficiency particulate air
pore size - 0.3 micrometer and used for bacterial cells, endospores, viruses
these types of ionizing radiation wavelengths are very lethal, penetrating sterilization, low level used on spices, meats, vegetables, high levels on medical supplies?
x-rays, electron beam, gamma rays
UV light acts as a _____?
bactericidal
what are the examples of ionizing radiation? non-ionizing?
gamma rays (for food) x-rays
infrared
microwaves
radio waves
increased wavelength going from ionizing to non ionizing
this type of wavelength crosslinks DNA creating thymine-thymine dimers, used for surface sterilization?
UV light
this type of wavelength excites water molecules and can be used to disinfect kitchen sponges?
microwaves
drying
salts/sugars
nitrates
what are these examples of?
food preservation methods
effectiveness in the chemical agents of microbial control depends on?
environmental
exposure time
microbial agent
T/F, disinfectants are sterilizing agents?
F, they are not
this scientist defined disinfection of equipment based on use?
Eagle Spaulding -1957
H2O2 alcohol 60-95% hypochlorite QUAT ionophore
is what level of disinfection?
low level disinfection
2% glutaraldehyde
6% H2O2
Pasteurization
0.2% per acetic acid
is what level of disinfection?
high level disinfection
this type of disinfecting and antiseptic chemical targets plasma membrane
i.e.- lysol, chlorhexidine, triclosan
phenolics
this type of disinfecting and antiseptic chemical disrupts membranes, denatures, and dehydrates
i.e.- hand sanitizers
alcohols
this type of disinfecting and antiseptic chemical inactivates proteins, destroys broad types of organisms and viruses
this specific element is used for tincture or ionophore and acts as a topical antisepsis
halogens
iodine
this type of disinfecting and antiseptic chemical combines with enzymes/proteins
broad variety of microorganisms
low concentrations can be applied in treatment for pathogenic infections
heavy metals
this is a type of synthetic surfactant that works by decreasing surface tension, disrupts lipid cell membranes, works by emulsification, wash hands for 30 seconds, rinse 10 seconds
soap
this type of disinfecting and antiseptic chemical is a positively charged detergent, so stronger surfactants, act against cell membrane, less toxic to humans, broad variety of microorganisms
quaternary ammonium compounds (quats; cationic detergents)
this type of disinfectant oxidizes cellular protein components
i.e. H2O2, benzoyl peroxide
what does H2O2 eliminate?Benzoyl peroxide?
peroxygens
anaerobic pathogens
acne treatments
this type of sterilant inactivates proteins and DNA, killing vegetative cells, viruses, and endospores, skin irritant
limited to sterilizing instruments and equipment?
aldehydes
this type of sterilant inactivates proteins and DNA
useful in sterilizing heat or moisture sensitive items, high penetration, kills spores and microbes
explosive, burns on contact with skin
sterilizing gases like ethylene oxide and choline dioxide
